diff --git a/labgrid/remote/client.py b/labgrid/remote/client.py
index 069240b9e..50150d50d 100755
--- a/labgrid/remote/client.py
+++ b/labgrid/remote/client.py
@@ -32,6 +32,11 @@
 # TODO: drop if Python >= 3.11 guaranteed
 from exceptiongroup import ExceptionGroup  # pylint: disable=redefined-builtin
 
+from labgrid.remote.grpc.interceptor.client import (
+    IdentityClientStreamStreamInterceptor,
+    IdentityClientUnaryUnaryInterceptor,
+)
+
 from .common import (
     ResourceEntry,
     ResourceMatch,
@@ -120,9 +125,19 @@ def __attrs_post_init__(self):
             ("grpc.http2.max_pings_without_data", 0),  # no limit
         ]
 
+        identity = {
+            "username": self.getuser(),
+            "hostname": self.gethostname(),
+            "user_agent": f"labgrid-client {labgrid_version()}",
+        }
+        interceptors = [
+            IdentityClientUnaryUnaryInterceptor(**identity),
+            IdentityClientStreamStreamInterceptor(**identity),
+        ]
         self.channel = grpc.aio.insecure_channel(
             target=self.address,
             options=channel_options,
+            interceptors=interceptors,
         )
         self.stub = labgrid_coordinator_pb2_grpc.CoordinatorStub(self.channel)
 
diff --git a/labgrid/remote/common.py b/labgrid/remote/common.py
index 14c8a2d74..3998733f3 100644
--- a/labgrid/remote/common.py
+++ b/labgrid/remote/common.py
@@ -7,6 +7,8 @@
 import logging
 from datetime import datetime
 from fnmatch import fnmatchcase
+from typing import Optional
+import warnings
 
 import attr
 
@@ -481,6 +483,21 @@ def from_pb2(cls, pb2: labgrid_coordinator_pb2.Reservation):
         )
 
 
+def get_metadata_single_value_by_key(metadata, key: str) -> Optional[str]:
+    """Look up a single value by key in a metadata sequence of (key, value) pairs."""
+    values = [v for k, v in metadata or () if k == key]
+
+    if not values:
+        return None
+
+    if len(values) > 1:
+        warnings.warn(
+            "Multiple metadata KV pairs with the same key. The value of the first matching KV pair will be returned."
+        )
+
+    return values[0]
+
+
 async def queue_as_aiter(q):
     try:
         while True:
diff --git a/labgrid/remote/coordinator.py b/labgrid/remote/coordinator.py
index 3423f3cef..03d96112b 100644
--- a/labgrid/remote/coordinator.py
+++ b/labgrid/remote/coordinator.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python3
 import argparse
+import contextvars
 import logging
 import asyncio
 import traceback
@@ -10,11 +11,15 @@
 import copy
 import random
 import signal
+from typing import Optional
 
 import attr
 import grpc
 from grpc_reflection.v1alpha import reflection
 
+from labgrid.remote.grpc.interceptor.server import IdentityServerInterceptor
+from labgrid.remote.identity import ClientIdentity, infer_peer_identity
+
 from .common import (
     ResourceEntry,
     ResourceMatch,
@@ -30,6 +35,10 @@
 from .generated import labgrid_coordinator_pb2_grpc
 from ..util import atomic_replace, labgrid_version, yaml, Timeout
 
+client_identity_context: contextvars.ContextVar[Optional[ClientIdentity]] = contextvars.ContextVar(
+    "client_identity", default=None
+)
+
 
 @contextmanager
 def warn_if_slow(prefix, *, level=logging.WARNING, limit=0.1):
@@ -317,9 +326,16 @@ async def ClientStream(self, request_iterator, context):
         assert peer not in self.clients
         out_msg_queue = asyncio.Queue()
 
+        identity = client_identity_context.get()
+        if identity:
+            logging.debug("client identity provided in gRPC metadata")
+            logging.debug(identity)
+            self.clients[peer] = ClientSession(self, peer, identity.id, out_msg_queue, identity.user_agent)
+
         async def request_task():
             name = None
             version = None
+            session = self.clients.get(peer)
             try:
                 async for in_msg in request_iterator:
                     in_msg: labgrid_coordinator_pb2.ClientInMessage
@@ -330,8 +346,18 @@ async def request_task():
                         out_msg.sync.id = in_msg.sync.id
                         out_msg_queue.put_nowait(out_msg)
                     elif kind == "startup":
-                        version = in_msg.startup.version
+                        if identity:
+                            logging.debug("ignoring legacy startup message; session initialised from metadata")
+                            continue
+                        if session:
+                            logging.warning("ignoring duplicate startup message from client %s", peer)
+                            continue
                         name = in_msg.startup.name
+                        version = in_msg.startup.version
+                        logging.warning(
+                            "client %s did not provide identity metadata; using deprecated startup identity",
+                            peer,
+                        )
                         session = self.clients[peer] = ClientSession(self, peer, name, out_msg_queue, version)
                         logging.debug("Received startup from %s with %s", name, version)
                         asyncio.current_task().set_name(f"client-{peer}-rx/started-{name}")
@@ -409,9 +435,22 @@ async def ExporterStream(self, request_iterator, context):
         out_msg.hello.version = labgrid_version()
         yield out_msg
 
+        identity = client_identity_context.get()
+        if identity:
+            logging.debug("exporter identity provided in gRPC metadata")
+            logging.debug(identity)
+            if existing := self.get_exporter_by_name(identity.id):
+                await context.abort(
+                    grpc.StatusCode.ALREADY_EXISTS,
+                    f"startup failed: exporter with name '{identity.id}' is already connected from {existing.peer}",
+                )
+            self.exporters[peer] = ExporterSession(self, peer, identity.id, command_queue, identity.user_agent)
+            startup_done.set()
+
         async def request_task():
             name = None
             version = None
+            session = self.exporters.get(peer)
             try:
                 async for in_msg in request_iterator:
                     in_msg: labgrid_coordinator_pb2.ExporterInMessage
@@ -422,8 +461,18 @@ async def request_task():
                         cmd.complete(in_msg.response)
                         logging.debug("Command %s is done", cmd)
                     elif kind == "startup":
-                        version = in_msg.startup.version
+                        if identity:
+                            logging.debug("ignoring legacy startup message; session initialized from metadata")
+                            continue
+                        if session:
+                            logging.warning("ignoring duplicate startup message from exporter %s", peer)
+                            continue
                         name = in_msg.startup.name
+                        version = in_msg.startup.version
+                        logging.warning(
+                            "exporter %s did not provide identity metadata; using deprecated startup identity",
+                            peer,
+                        )
                         if existing := self.get_exporter_by_name(name):
                             raise ExporterError(
                                 f"exporter with name '{name}' is already connected from {existing.peer}"
@@ -852,7 +901,7 @@ async def AcquirePlace(self, request, context):
         peer = context.peer()
         name = request.placename
         try:
-            username = self.clients[peer].name
+            username = infer_peer_identity(self.clients, context, client_identity_context)
         except KeyError:
             await context.abort(grpc.StatusCode.FAILED_PRECONDITION, f"Peer {peer} does not have a valid session")
         print(request)
@@ -922,7 +971,7 @@ async def AllowPlace(self, request, context):
         user = request.user
         peer = context.peer()
         try:
-            username = self.clients[peer].name
+            username = infer_peer_identity(self.clients, context, client_identity_context)
         except KeyError:
             await context.abort(grpc.StatusCode.FAILED_PRECONDITION, f"Peer {peer} does not have a valid session")
         try:
@@ -1077,7 +1126,10 @@ async def CreateReservation(self, request: labgrid_coordinator_pb2.CreateReserva
                     await context.abort(grpc.StatusCode.INVALID_ARGUMENT, f"Value {v} is invalid")
                 fltr[k] = v
 
-        owner = self.clients[peer].name
+        try:
+            owner = infer_peer_identity(self.clients, context, client_identity_context)
+        except KeyError:
+            await context.abort(grpc.StatusCode.FAILED_PRECONDITION, f"Peer {peer} does not have a valid session")
         res = Reservation(owner=owner, prio=request.prio, filters=fltrs)
         self.reservations[res.token] = res
         self.schedule_reservations()
@@ -1127,6 +1179,7 @@ async def serve(listen, cleanup) -> None:
     ]
     server = grpc.aio.server(
         options=channel_options,
+        interceptors=[IdentityServerInterceptor(client_identity_context)],
     )
     coordinator = Coordinator()
     labgrid_coordinator_pb2_grpc.add_CoordinatorServicer_to_server(coordinator, server)
diff --git a/labgrid/remote/exporter.py b/labgrid/remote/exporter.py
index 82f1da6b6..5cf149803 100755
--- a/labgrid/remote/exporter.py
+++ b/labgrid/remote/exporter.py
@@ -20,6 +20,11 @@
 import attr
 import grpc
 
+from labgrid.remote.grpc.interceptor.client import (
+    IdentityClientStreamStreamInterceptor,
+    IdentityClientUnaryUnaryInterceptor,
+)
+
 from .config import ResourceConfig
 from .common import ResourceEntry, queue_as_aiter
 from .generated import labgrid_coordinator_pb2, labgrid_coordinator_pb2_grpc
@@ -834,9 +839,14 @@ def __init__(self, config) -> None:
         if urlsplit(f"//{config['coordinator']}").port is None:
             config["coordinator"] += ":20408"
 
+        identity = (None, self.name, f"labgrid-exporter {labgrid_version()}")
         self.channel = grpc.aio.insecure_channel(
             target=config["coordinator"],
             options=channel_options,
+            interceptors=[
+                IdentityClientUnaryUnaryInterceptor(*identity),
+                IdentityClientStreamStreamInterceptor(*identity),
+            ],
         )
         self.stub = labgrid_coordinator_pb2_grpc.CoordinatorStub(self.channel)
         self.out_queue = asyncio.Queue()
diff --git a/labgrid/remote/generated/labgrid_coordinator_pb2.py b/labgrid/remote/generated/labgrid_coordinator_pb2.py
index 37652bff7..6c75474f7 100644
--- a/labgrid/remote/generated/labgrid_coordinator_pb2.py
+++ b/labgrid/remote/generated/labgrid_coordinator_pb2.py
@@ -14,13 +14,19 @@
 
 
 
-DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x19labgrid-coordinator.proto\x12\x07labgrid\"\x8a\x01\n\x0f\x43lientInMessage\x12\x1d\n\x04sync\x18\x01 \x01(\x0b\x32\r.labgrid.SyncH\x00\x12\'\n\x07startup\x18\x02 \x01(\x0b\x32\x14.labgrid.StartupDoneH\x00\x12\'\n\tsubscribe\x18\x03 \x01(\x0b\x32\x12.labgrid.SubscribeH\x00\x42\x06\n\x04kind\"\x12\n\x04Sync\x12\n\n\x02id\x18\x01 \x01(\x04\",\n\x0bStartupDone\x12\x0f\n\x07version\x18\x01 \x01(\t\x12\x0c\n\x04name\x18\x02 \x01(\t\"r\n\tSubscribe\x12\x1b\n\x0eis_unsubscribe\x18\x01 \x01(\x08H\x01\x88\x01\x01\x12\x14\n\nall_places\x18\x02 \x01(\x08H\x00\x12\x17\n\rall_resources\x18\x03 \x01(\x08H\x00\x42\x06\n\x04kindB\x11\n\x0f_is_unsubscribe\"g\n\x10\x43lientOutMessage\x12 \n\x04sync\x18\x01 \x01(\x0b\x32\r.labgrid.SyncH\x00\x88\x01\x01\x12(\n\x07updates\x18\x02 \x03(\x0b\x32\x17.labgrid.UpdateResponseB\x07\n\x05_sync\"\xa5\x01\n\x0eUpdateResponse\x12%\n\x08resource\x18\x01 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\x03(\x0b\x32\x14.labgrid.Reservation\"\x18\n\x16GetReservationsRequest2\xd2\x0b\n\x0b\x43oordinator\x12I\n\x0c\x43lientStream\x12\x18.labgrid.ClientInMessage\x1a\x19.labgrid.ClientOutMessage\"\x00(\x01\x30\x01\x12O\n\x0e\x45xporterStream\x12\x1a.labgrid.ExporterInMessage\x1a\x1b.labgrid.ExporterOutMessage\"\x00(\x01\x30\x01\x12\x41\n\x08\x41\x64\x64Place\x12\x18.labgrid.AddPlaceRequest\x1a\x19.labgrid.AddPlaceResponse\"\x00\x12J\n\x0b\x44\x65letePlace\x12\x1b.labgrid.DeletePlaceRequest\x1a\x1c.labgrid.DeletePlaceResponse\"\x00\x12\x44\n\tGetPlaces\x12\x19.labgrid.GetPlacesRequest\x1a\x1a.labgrid.GetPlacesResponse\"\x00\x12P\n\rAddPlaceAlias\x12\x1d.labgrid.AddPlaceAliasRequest\x1a\x1e.labgrid.AddPlaceAliasResponse\"\x00\x12Y\n\x10\x44\x65letePlaceAlias\x12 .labgrid.DeletePlaceAliasRequest\x1a!.labgrid.DeletePlaceAliasResponse\"\x00\x12M\n\x0cSetPlaceTags\x12\x1c.labgrid.SetPlaceTagsRequest\x1a\x1d.labgrid.SetPlaceTagsResponse\"\x00\x12V\n\x0fSetPlaceComment\x12\x1f.labgrid.SetPlaceCommentRequest\x1a .labgrid.SetPlaceCommentResponse\"\x00\x12P\n\rAddPlaceMatch\x12\x1d.labgrid.AddPlaceMatchRequest\x1a\x1e.labgrid.AddPlaceMatchResponse\"\x00\x12Y\n\x10\x44\x65letePlaceMatch\x12 .labgrid.DeletePlaceMatchRequest\x1a!.labgrid.DeletePlaceMatchResponse\"\x00\x12M\n\x0c\x41\x63quirePlace\x12\x1c.labgrid.AcquirePlaceRequest\x1a\x1d.labgrid.AcquirePlaceResponse\"\x00\x12M\n\x0cReleasePlace\x12\x1c.labgrid.ReleasePlaceRequest\x1a\x1d.labgrid.ReleasePlaceResponse\"\x00\x12G\n\nAllowPlace\x12\x1a.labgrid.AllowPlaceRequest\x1a\x1b.labgrid.AllowPlaceResponse\"\x00\x12\\\n\x11\x43reateReservation\x12!.labgrid.CreateReservationRequest\x1a\".labgrid.CreateReservationResponse\"\x00\x12\\\n\x11\x43\x61ncelReservation\x12!.labgrid.CancelReservationRequest\x1a\".labgrid.CancelReservationResponse\"\x00\x12V\n\x0fPollReservation\x12\x1f.labgrid.PollReservationRequest\x1a .labgrid.PollReservationResponse\"\x00\x12V\n\x0fGetReservations\x12\x1f.labgrid.GetReservationsRequest\x1a .labgrid.GetReservationsResponse\"\x00\x62\x06proto3')
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x19labgrid-coordinator.proto\x12\x07labgrid\"\x8e\x01\n\x0f\x43lientInMessage\x12\x1d\n\x04sync\x18\x01 \x01(\x0b\x32\r.labgrid.SyncH\x00\x12+\n\x07startup\x18\x02 \x01(\x0b\x32\x14.labgrid.StartupDoneB\x02\x18\x01H\x00\x12\'\n\tsubscribe\x18\x03 \x01(\x0b\x32\x12.labgrid.SubscribeH\x00\x42\x06\n\x04kind\"\x12\n\x04Sync\x12\n\n\x02id\x18\x01 \x01(\x04\"0\n\x0bStartupDone\x12\x0f\n\x07version\x18\x01 \x01(\t\x12\x0c\n\x04name\x18\x02 \x01(\t:\x02\x18\x01\"r\n\tSubscribe\x12\x1b\n\x0eis_unsubscribe\x18\x01 \x01(\x08H\x01\x88\x01\x01\x12\x14\n\nall_places\x18\x02 \x01(\x08H\x00\x12\x17\n\rall_resources\x18\x03 \x01(\x08H\x00\x42\x06\n\x04kindB\x11\n\x0f_is_unsubscribe\"g\n\x10\x43lientOutMessage\x12 \n\x04sync\x18\x01 \x01(\x0b\x32\r.labgrid.SyncH\x00\x88\x01\x01\x12(\n\x07updates\x18\x02 \x03(\x0b\x32\x17.labgrid.UpdateResponseB\x07\n\x05_sync\"\xa5\x01\n\x0eUpdateResponse\x12%\n\x08resource\x18\x01 \x01(\x0b\x32\x11.labgrid.ResourceH\x00\x12.\n\x0c\x64\x65l_resource\x18\x02 \x01(\x0b\x32\x16.labgrid.Resource.PathH\x00\x12\x1f\n\x05place\x18\x03 \x01(\x0b\x32\x0e.labgrid.PlaceH\x00\x12\x13\n\tdel_place\x18\x04 \x01(\tH\x00\x42\x06\n\x04kind\"\x9e\x01\n\x11\x45xporterInMessage\x12%\n\x08resource\x18\x01 \x01(\x0b\x32\x11.labgrid.ResourceH\x00\x12+\n\x07startup\x18\x02 \x01(\x0b\x32\x14.labgrid.StartupDoneB\x02\x18\x01H\x00\x12-\n\x08response\x18\x03 \x01(\x0b\x32\x19.labgrid.ExporterResponseH\x00\x42\x06\n\x04kind\"\x9e\x03\n\x08Resource\x12$\n\x04path\x18\x01 \x01(\x0b\x32\x16.labgrid.Resource.Path\x12\x0b\n\x03\x63ls\x18\x02 \x01(\t\x12-\n\x06params\x18\x03 \x03(\x0b\x32\x1d.labgrid.Resource.ParamsEntry\x12+\n\x05\x65xtra\x18\x04 \x03(\x0b\x32\x1c.labgrid.Resource.ExtraEntry\x12\x10\n\x08\x61\x63quired\x18\x05 \x01(\t\x12\r\n\x05\x61vail\x18\x06 \x01(\x08\x1a_\n\x04Path\x12\x1a\n\rexporter_name\x18\x01 \x01(\tH\x00\x88\x01\x01\x12\x12\n\ngroup_name\x18\x02 \x01(\t\x12\x15\n\rresource_name\x18\x03 \x01(\tB\x10\n\x0e_exporter_name\x1a@\n\x0bParamsEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12 \n\x05value\x18\x02 \x01(\x0b\x32\x11.labgrid.MapValue:\x02\x38\x01\x1a?\n\nExtraEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12 \n\x05value\x18\x02 \x01(\x0b\x32\x11.labgrid.MapValue:\x02\x38\x01\"\x82\x01\n\x08MapValue\x12\x14\n\nbool_value\x18\x01 \x01(\x08H\x00\x12\x13\n\tint_value\x18\x02 \x01(\x03H\x00\x12\x14\n\nuint_value\x18\x03 \x01(\x04H\x00\x12\x15\n\x0b\x66loat_value\x18\x04 \x01(\x01H\x00\x12\x16\n\x0cstring_value\x18\x05 \x01(\tH\x00\x42\x06\n\x04kind\"C\n\x10\x45xporterResponse\x12\x0f\n\x07success\x18\x01 \x01(\x08\x12\x13\n\x06reason\x18\x02 \x01(\tH\x00\x88\x01\x01\x42\t\n\x07_reason\"\x18\n\x05Hello\x12\x0f\n\x07version\x18\x01 \x01(\t\"\x82\x01\n\x12\x45xporterOutMessage\x12\x1f\n\x05hello\x18\x01 \x01(\x0b\x32\x0e.labgrid.HelloH\x00\x12\x43\n\x14set_acquired_request\x18\x02 \x01(\x0b\x32#.labgrid.ExporterSetAcquiredRequestH\x00\x42\x06\n\x04kind\"o\n\x1a\x45xporterSetAcquiredRequest\x12\x12\n\ngroup_name\x18\x01 \x01(\t\x12\x15\n\rresource_name\x18\x02 \x01(\t\x12\x17\n\nplace_name\x18\x03 \x01(\tH\x00\x88\x01\x01\x42\r\n\x0b_place_name\"\x1f\n\x0f\x41\x64\x64PlaceRequest\x12\x0c\n\x04name\x18\x01 \x01(\t\"\x12\n\x10\x41\x64\x64PlaceResponse\"\"\n\x12\x44\x65letePlaceRequest\x12\x0c\n\x04name\x18\x01 \x01(\t\"\x15\n\x13\x44\x65letePlaceResponse\"\x12\n\x10GetPlacesRequest\"3\n\x11GetPlacesResponse\x12\x1e\n\x06places\x18\x01 \x03(\x0b\x32\x0e.labgrid.Place\"\xd2\x02\n\x05Place\x12\x0c\n\x04name\x18\x01 \x01(\t\x12\x0f\n\x07\x61liases\x18\x02 \x03(\t\x12\x0f\n\x07\x63omment\x18\x03 \x01(\t\x12&\n\x04tags\x18\x04 \x03(\x0b\x32\x18.labgrid.Place.TagsEntry\x12\'\n\x07matches\x18\x05 \x03(\x0b\x32\x16.labgrid.ResourceMatch\x12\x15\n\x08\x61\x63quired\x18\x06 \x01(\tH\x00\x88\x01\x01\x12\x1a\n\x12\x61\x63quired_resources\x18\x07 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\x03(\x0b\x32&.labgrid.SetPlaceTagsRequest.TagsEntry\x1a+\n\tTagsEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12\r\n\x05value\x18\x02 \x01(\t:\x02\x38\x01\"\x16\n\x14SetPlaceTagsResponse\"<\n\x16SetPlaceCommentRequest\x12\x11\n\tplacename\x18\x01 \x01(\t\x12\x0f\n\x07\x63omment\x18\x02 \x01(\t\"\x19\n\x17SetPlaceCommentResponse\"Z\n\x14\x41\x64\x64PlaceMatchRequest\x12\x11\n\tplacename\x18\x01 \x01(\t\x12\x0f\n\x07pattern\x18\x02 \x01(\t\x12\x13\n\x06rename\x18\x03 \x01(\tH\x00\x88\x01\x01\x42\t\n\x07_rename\"\x17\n\x15\x41\x64\x64PlaceMatchResponse\"]\n\x17\x44\x65letePlaceMatchRequest\x12\x11\n\tplacename\x18\x01 \x01(\t\x12\x0f\n\x07pattern\x18\x02 \x01(\t\x12\x13\n\x06rename\x18\x03 \x01(\tH\x00\x88\x01\x01\x42\t\n\x07_rename\"\x1a\n\x18\x44\x65letePlaceMatchResponse\"(\n\x13\x41\x63quirePlaceRequest\x12\x11\n\tplacename\x18\x01 \x01(\t\"\x16\n\x14\x41\x63quirePlaceResponse\"L\n\x13ReleasePlaceRequest\x12\x11\n\tplacename\x18\x01 \x01(\t\x12\x15\n\x08\x66romuser\x18\x02 \x01(\tH\x00\x88\x01\x01\x42\x0b\n\t_fromuser\"\x16\n\x14ReleasePlaceResponse\"4\n\x11\x41llowPlaceRequest\x12\x11\n\tplacename\x18\x01 \x01(\t\x12\x0c\n\x04user\x18\x02 \x01(\t\"\x14\n\x12\x41llowPlaceResponse\"\xb6\x01\n\x18\x43reateReservationRequest\x12?\n\x07\x66ilters\x18\x01 \x03(\x0b\x32..labgrid.CreateReservationRequest.FiltersEntry\x12\x0c\n\x04prio\x18\x02 \x01(\x01\x1aK\n\x0c\x46iltersEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12*\n\x05value\x18\x02 \x01(\x0b\x32\x1b.labgrid.Reservation.Filter:\x02\x38\x01\"F\n\x19\x43reateReservationResponse\x12)\n\x0breservation\x18\x01 \x01(\x0b\x32\x14.labgrid.Reservation\"\xcd\x03\n\x0bReservation\x12\r\n\x05owner\x18\x01 \x01(\t\x12\r\n\x05token\x18\x02 \x01(\t\x12\r\n\x05state\x18\x03 \x01(\x05\x12\x0c\n\x04prio\x18\x04 \x01(\x01\x12\x32\n\x07\x66ilters\x18\x05 \x03(\x0b\x32!.labgrid.Reservation.FiltersEntry\x12:\n\x0b\x61llocations\x18\x06 \x03(\x0b\x32%.labgrid.Reservation.AllocationsEntry\x12\x0f\n\x07\x63reated\x18\x07 \x01(\x01\x12\x0f\n\x07timeout\x18\x08 \x01(\x01\x1ap\n\x06\x46ilter\x12\x37\n\x06\x66ilter\x18\x01 \x03(\x0b\x32\'.labgrid.Reservation.Filter.FilterEntry\x1a-\n\x0b\x46ilterEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12\r\n\x05value\x18\x02 \x01(\t:\x02\x38\x01\x1aK\n\x0c\x46iltersEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12*\n\x05value\x18\x02 \x01(\x0b\x32\x1b.labgrid.Reservation.Filter:\x02\x38\x01\x1a\x32\n\x10\x41llocationsEntry\x12\x0b\n\x03key\x18\x01 \x01(\t\x12\r\n\x05value\x18\x02 \x01(\t:\x02\x38\x01\")\n\x18\x43\x61ncelReservationRequest\x12\r\n\x05token\x18\x01 \x01(\t\"\x1b\n\x19\x43\x61ncelReservationResponse\"\'\n\x16PollReservationRequest\x12\r\n\x05token\x18\x01 \x01(\t\"D\n\x17PollReservationResponse\x12)\n\x0breservation\x18\x01 \x01(\x0b\x32\x14.labgrid.Reservation\"E\n\x17GetReservationsResponse\x12*\n\x0creservations\x18\x01 \x03(\x0b\x32\x14.labgrid.Reservation\"\x18\n\x16GetReservationsRequest2\xd2\x0b\n\x0b\x43oordinator\x12I\n\x0c\x43lientStream\x12\x18.labgrid.ClientInMessage\x1a\x19.labgrid.ClientOutMessage\"\x00(\x01\x30\x01\x12O\n\x0e\x45xporterStream\x12\x1a.labgrid.ExporterInMessage\x1a\x1b.labgrid.ExporterOutMessage\"\x00(\x01\x30\x01\x12\x41\n\x08\x41\x64\x64Place\x12\x18.labgrid.AddPlaceRequest\x1a\x19.labgrid.AddPlaceResponse\"\x00\x12J\n\x0b\x44\x65letePlace\x12\x1b.labgrid.DeletePlaceRequest\x1a\x1c.labgrid.DeletePlaceResponse\"\x00\x12\x44\n\tGetPlaces\x12\x19.labgrid.GetPlacesRequest\x1a\x1a.labgrid.GetPlacesResponse\"\x00\x12P\n\rAddPlaceAlias\x12\x1d.labgrid.AddPlaceAliasRequest\x1a\x1e.labgrid.AddPlaceAliasResponse\"\x00\x12Y\n\x10\x44\x65letePlaceAlias\x12 .labgrid.DeletePlaceAliasRequest\x1a!.labgrid.DeletePlaceAliasResponse\"\x00\x12M\n\x0cSetPlaceTags\x12\x1c.labgrid.SetPlaceTagsRequest\x1a\x1d.labgrid.SetPlaceTagsResponse\"\x00\x12V\n\x0fSetPlaceComment\x12\x1f.labgrid.SetPlaceCommentRequest\x1a .labgrid.SetPlaceCommentResponse\"\x00\x12P\n\rAddPlaceMatch\x12\x1d.labgrid.AddPlaceMatchRequest\x1a\x1e.labgrid.AddPlaceMatchResponse\"\x00\x12Y\n\x10\x44\x65letePlaceMatch\x12 .labgrid.DeletePlaceMatchRequest\x1a!.labgrid.DeletePlaceMatchResponse\"\x00\x12M\n\x0c\x41\x63quirePlace\x12\x1c.labgrid.AcquirePlaceRequest\x1a\x1d.labgrid.AcquirePlaceResponse\"\x00\x12M\n\x0cReleasePlace\x12\x1c.labgrid.ReleasePlaceRequest\x1a\x1d.labgrid.ReleasePlaceResponse\"\x00\x12G\n\nAllowPlace\x12\x1a.labgrid.AllowPlaceRequest\x1a\x1b.labgrid.AllowPlaceResponse\"\x00\x12\\\n\x11\x43reateReservation\x12!.labgrid.CreateReservationRequest\x1a\".labgrid.CreateReservationResponse\"\x00\x12\\\n\x11\x43\x61ncelReservation\x12!.labgrid.CancelReservationRequest\x1a\".labgrid.CancelReservationResponse\"\x00\x12V\n\x0fPollReservation\x12\x1f.labgrid.PollReservationRequest\x1a .labgrid.PollReservationResponse\"\x00\x12V\n\x0fGetReservations\x12\x1f.labgrid.GetReservationsRequest\x1a .labgrid.GetReservationsResponse\"\x00\x62\x06proto3')
 
 _globals = globals()
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
 _builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'labgrid_coordinator_pb2', _globals)
 if _descriptor._USE_C_DESCRIPTORS == False:
   DESCRIPTOR._options = None
+  _globals['_CLIENTINMESSAGE'].fields_by_name['startup']._options = None
+  _globals['_CLIENTINMESSAGE'].fields_by_name['startup']._serialized_options = b'\030\001'
+  _globals['_STARTUPDONE']._options = None
+  _globals['_STARTUPDONE']._serialized_options = b'\030\001'
+  _globals['_EXPORTERINMESSAGE'].fields_by_name['startup']._options = None
+  _globals['_EXPORTERINMESSAGE'].fields_by_name['startup']._serialized_options = b'\030\001'
   _globals['_RESOURCE_PARAMSENTRY']._options = None
   _globals['_RESOURCE_PARAMSENTRY']._serialized_options = b'8\001'
   _globals['_RESOURCE_EXTRAENTRY']._options = None
@@ -38,121 +44,121 @@
   _globals['_RESERVATION_ALLOCATIONSENTRY']._options = None
   _globals['_RESERVATION_ALLOCATIONSENTRY']._serialized_options = b'8\001'
   _globals['_CLIENTINMESSAGE']._serialized_start=39
-  _globals['_CLIENTINMESSAGE']._serialized_end=177
-  _globals['_SYNC']._serialized_start=179
-  _globals['_SYNC']._serialized_end=197
-  _globals['_STARTUPDONE']._serialized_start=199
-  _globals['_STARTUPDONE']._serialized_end=243
-  _globals['_SUBSCRIBE']._serialized_start=245
-  _globals['_SUBSCRIBE']._serialized_end=359
-  _globals['_CLIENTOUTMESSAGE']._serialized_start=361
-  _globals['_CLIENTOUTMESSAGE']._serialized_end=464
-  _globals['_UPDATERESPONSE']._serialized_start=467
-  _globals['_UPDATERESPONSE']._serialized_end=632
-  _globals['_EXPORTERINMESSAGE']._serialized_start=635
-  _globals['_EXPORTERINMESSAGE']._serialized_end=789
-  _globals['_RESOURCE']._serialized_start=792
-  _globals['_RESOURCE']._serialized_end=1206
-  _globals['_RESOURCE_PATH']._serialized_start=980
-  _globals['_RESOURCE_PATH']._serialized_end=1075
-  _globals['_RESOURCE_PARAMSENTRY']._serialized_start=1077
-  _globals['_RESOURCE_PARAMSENTRY']._serialized_end=1141
-  _globals['_RESOURCE_EXTRAENTRY']._serialized_start=1143
-  _globals['_RESOURCE_EXTRAENTRY']._serialized_end=1206
-  _globals['_MAPVALUE']._serialized_start=1209
-  _globals['_MAPVALUE']._serialized_end=1339
-  _globals['_EXPORTERRESPONSE']._serialized_start=1341
-  _globals['_EXPORTERRESPONSE']._serialized_end=1408
-  _globals['_HELLO']._serialized_start=1410
-  _globals['_HELLO']._serialized_end=1434
-  _globals['_EXPORTEROUTMESSAGE']._serialized_start=1437
-  _globals['_EXPORTEROUTMESSAGE']._serialized_end=1567
-  _globals['_EXPORTERSETACQUIREDREQUEST']._serialized_start=1569
-  _globals['_EXPORTERSETACQUIREDREQUEST']._serialized_end=1680
-  _globals['_ADDPLACEREQUEST']._serialized_start=1682
-  _globals['_ADDPLACEREQUEST']._serialized_end=1713
-  _globals['_ADDPLACERESPONSE']._serialized_start=1715
-  _globals['_ADDPLACERESPONSE']._serialized_end=1733
-  _globals['_DELETEPLACEREQUEST']._serialized_start=1735
-  _globals['_DELETEPLACEREQUEST']._serialized_end=1769
-  _globals['_DELETEPLACERESPONSE']._serialized_start=1771
-  _globals['_DELETEPLACERESPONSE']._serialized_end=1792
-  _globals['_GETPLACESREQUEST']._serialized_start=1794
-  _globals['_GETPLACESREQUEST']._serialized_end=1812
-  _globals['_GETPLACESRESPONSE']._serialized_start=1814
-  _globals['_GETPLACESRESPONSE']._serialized_end=1865
-  _globals['_PLACE']._serialized_start=1868
-  _globals['_PLACE']._serialized_end=2206
-  _globals['_PLACE_TAGSENTRY']._serialized_start=2134
-  _globals['_PLACE_TAGSENTRY']._serialized_end=2177
-  _globals['_RESOURCEMATCH']._serialized_start=2208
-  _globals['_RESOURCEMATCH']._serialized_end=2329
-  _globals['_ADDPLACEALIASREQUEST']._serialized_start=2331
-  _globals['_ADDPLACEALIASREQUEST']._serialized_end=2387
-  _globals['_ADDPLACEALIASRESPONSE']._serialized_start=2389
-  _globals['_ADDPLACEALIASRESPONSE']._serialized_end=2412
-  _globals['_DELETEPLACEALIASREQUEST']._serialized_start=2414
-  _globals['_DELETEPLACEALIASREQUEST']._serialized_end=2473
-  _globals['_DELETEPLACEALIASRESPONSE']._serialized_start=2475
-  _globals['_DELETEPLACEALIASRESPONSE']._serialized_end=2501
-  _globals['_SETPLACETAGSREQUEST']._serialized_start=2504
-  _globals['_SETPLACETAGSREQUEST']._serialized_end=2643
-  _globals['_SETPLACETAGSREQUEST_TAGSENTRY']._serialized_start=2134
-  _globals['_SETPLACETAGSREQUEST_TAGSENTRY']._serialized_end=2177
-  _globals['_SETPLACETAGSRESPONSE']._serialized_start=2645
-  _globals['_SETPLACETAGSRESPONSE']._serialized_end=2667
-  _globals['_SETPLACECOMMENTREQUEST']._serialized_start=2669
-  _globals['_SETPLACECOMMENTREQUEST']._serialized_end=2729
-  _globals['_SETPLACECOMMENTRESPONSE']._serialized_start=2731
-  _globals['_SETPLACECOMMENTRESPONSE']._serialized_end=2756
-  _globals['_ADDPLACEMATCHREQUEST']._serialized_start=2758
-  _globals['_ADDPLACEMATCHREQUEST']._serialized_end=2848
-  _globals['_ADDPLACEMATCHRESPONSE']._serialized_start=2850
-  _globals['_ADDPLACEMATCHRESPONSE']._serialized_end=2873
-  _globals['_DELETEPLACEMATCHREQUEST']._serialized_start=2875
-  _globals['_DELETEPLACEMATCHREQUEST']._serialized_end=2968
-  _globals['_DELETEPLACEMATCHRESPONSE']._serialized_start=2970
-  _globals['_DELETEPLACEMATCHRESPONSE']._serialized_end=2996
-  _globals['_ACQUIREPLACEREQUEST']._serialized_start=2998
-  _globals['_ACQUIREPLACEREQUEST']._serialized_end=3038
-  _globals['_ACQUIREPLACERESPONSE']._serialized_start=3040
-  _globals['_ACQUIREPLACERESPONSE']._serialized_end=3062
-  _globals['_RELEASEPLACEREQUEST']._serialized_start=3064
-  _globals['_RELEASEPLACEREQUEST']._serialized_end=3140
-  _globals['_RELEASEPLACERESPONSE']._serialized_start=3142
-  _globals['_RELEASEPLACERESPONSE']._serialized_end=3164
-  _globals['_ALLOWPLACEREQUEST']._serialized_start=3166
-  _globals['_ALLOWPLACEREQUEST']._serialized_end=3218
-  _globals['_ALLOWPLACERESPONSE']._serialized_start=3220
-  _globals['_ALLOWPLACERESPONSE']._serialized_end=3240
-  _globals['_CREATERESERVATIONREQUEST']._serialized_start=3243
-  _globals['_CREATERESERVATIONREQUEST']._serialized_end=3425
-  _globals['_CREATERESERVATIONREQUEST_FILTERSENTRY']._serialized_start=3350
-  _globals['_CREATERESERVATIONREQUEST_FILTERSENTRY']._serialized_end=3425
-  _globals['_CREATERESERVATIONRESPONSE']._serialized_start=3427
-  _globals['_CREATERESERVATIONRESPONSE']._serialized_end=3497
-  _globals['_RESERVATION']._serialized_start=3500
-  _globals['_RESERVATION']._serialized_end=3961
-  _globals['_RESERVATION_FILTER']._serialized_start=3720
-  _globals['_RESERVATION_FILTER']._serialized_end=3832
-  _globals['_RESERVATION_FILTER_FILTERENTRY']._serialized_start=3787
-  _globals['_RESERVATION_FILTER_FILTERENTRY']._serialized_end=3832
-  _globals['_RESERVATION_FILTERSENTRY']._serialized_start=3350
-  _globals['_RESERVATION_FILTERSENTRY']._serialized_end=3425
-  _globals['_RESERVATION_ALLOCATIONSENTRY']._serialized_start=3911
-  _globals['_RESERVATION_ALLOCATIONSENTRY']._serialized_end=3961
-  _globals['_CANCELRESERVATIONREQUEST']._serialized_start=3963
-  _globals['_CANCELRESERVATIONREQUEST']._serialized_end=4004
-  _globals['_CANCELRESERVATIONRESPONSE']._serialized_start=4006
-  _globals['_CANCELRESERVATIONRESPONSE']._serialized_end=4033
-  _globals['_POLLRESERVATIONREQUEST']._serialized_start=4035
-  _globals['_POLLRESERVATIONREQUEST']._serialized_end=4074
-  _globals['_POLLRESERVATIONRESPONSE']._serialized_start=4076
-  _globals['_POLLRESERVATIONRESPONSE']._serialized_end=4144
-  _globals['_GETRESERVATIONSRESPONSE']._serialized_start=4146
-  _globals['_GETRESERVATIONSRESPONSE']._serialized_end=4215
-  _globals['_GETRESERVATIONSREQUEST']._serialized_start=4217
-  _globals['_GETRESERVATIONSREQUEST']._serialized_end=4241
-  _globals['_COORDINATOR']._serialized_start=4244
-  _globals['_COORDINATOR']._serialized_end=5734
+  _globals['_CLIENTINMESSAGE']._serialized_end=181
+  _globals['_SYNC']._serialized_start=183
+  _globals['_SYNC']._serialized_end=201
+  _globals['_STARTUPDONE']._serialized_start=203
+  _globals['_STARTUPDONE']._serialized_end=251
+  _globals['_SUBSCRIBE']._serialized_start=253
+  _globals['_SUBSCRIBE']._serialized_end=367
+  _globals['_CLIENTOUTMESSAGE']._serialized_start=369
+  _globals['_CLIENTOUTMESSAGE']._serialized_end=472
+  _globals['_UPDATERESPONSE']._serialized_start=475
+  _globals['_UPDATERESPONSE']._serialized_end=640
+  _globals['_EXPORTERINMESSAGE']._serialized_start=643
+  _globals['_EXPORTERINMESSAGE']._serialized_end=801
+  _globals['_RESOURCE']._serialized_start=804
+  _globals['_RESOURCE']._serialized_end=1218
+  _globals['_RESOURCE_PATH']._serialized_start=992
+  _globals['_RESOURCE_PATH']._serialized_end=1087
+  _globals['_RESOURCE_PARAMSENTRY']._serialized_start=1089
+  _globals['_RESOURCE_PARAMSENTRY']._serialized_end=1153
+  _globals['_RESOURCE_EXTRAENTRY']._serialized_start=1155
+  _globals['_RESOURCE_EXTRAENTRY']._serialized_end=1218
+  _globals['_MAPVALUE']._serialized_start=1221
+  _globals['_MAPVALUE']._serialized_end=1351
+  _globals['_EXPORTERRESPONSE']._serialized_start=1353
+  _globals['_EXPORTERRESPONSE']._serialized_end=1420
+  _globals['_HELLO']._serialized_start=1422
+  _globals['_HELLO']._serialized_end=1446
+  _globals['_EXPORTEROUTMESSAGE']._serialized_start=1449
+  _globals['_EXPORTEROUTMESSAGE']._serialized_end=1579
+  _globals['_EXPORTERSETACQUIREDREQUEST']._serialized_start=1581
+  _globals['_EXPORTERSETACQUIREDREQUEST']._serialized_end=1692
+  _globals['_ADDPLACEREQUEST']._serialized_start=1694
+  _globals['_ADDPLACEREQUEST']._serialized_end=1725
+  _globals['_ADDPLACERESPONSE']._serialized_start=1727
+  _globals['_ADDPLACERESPONSE']._serialized_end=1745
+  _globals['_DELETEPLACEREQUEST']._serialized_start=1747
+  _globals['_DELETEPLACEREQUEST']._serialized_end=1781
+  _globals['_DELETEPLACERESPONSE']._serialized_start=1783
+  _globals['_DELETEPLACERESPONSE']._serialized_end=1804
+  _globals['_GETPLACESREQUEST']._serialized_start=1806
+  _globals['_GETPLACESREQUEST']._serialized_end=1824
+  _globals['_GETPLACESRESPONSE']._serialized_start=1826
+  _globals['_GETPLACESRESPONSE']._serialized_end=1877
+  _globals['_PLACE']._serialized_start=1880
+  _globals['_PLACE']._serialized_end=2218
+  _globals['_PLACE_TAGSENTRY']._serialized_start=2146
+  _globals['_PLACE_TAGSENTRY']._serialized_end=2189
+  _globals['_RESOURCEMATCH']._serialized_start=2220
+  _globals['_RESOURCEMATCH']._serialized_end=2341
+  _globals['_ADDPLACEALIASREQUEST']._serialized_start=2343
+  _globals['_ADDPLACEALIASREQUEST']._serialized_end=2399
+  _globals['_ADDPLACEALIASRESPONSE']._serialized_start=2401
+  _globals['_ADDPLACEALIASRESPONSE']._serialized_end=2424
+  _globals['_DELETEPLACEALIASREQUEST']._serialized_start=2426
+  _globals['_DELETEPLACEALIASREQUEST']._serialized_end=2485
+  _globals['_DELETEPLACEALIASRESPONSE']._serialized_start=2487
+  _globals['_DELETEPLACEALIASRESPONSE']._serialized_end=2513
+  _globals['_SETPLACETAGSREQUEST']._serialized_start=2516
+  _globals['_SETPLACETAGSREQUEST']._serialized_end=2655
+  _globals['_SETPLACETAGSREQUEST_TAGSENTRY']._serialized_start=2146
+  _globals['_SETPLACETAGSREQUEST_TAGSENTRY']._serialized_end=2189
+  _globals['_SETPLACETAGSRESPONSE']._serialized_start=2657
+  _globals['_SETPLACETAGSRESPONSE']._serialized_end=2679
+  _globals['_SETPLACECOMMENTREQUEST']._serialized_start=2681
+  _globals['_SETPLACECOMMENTREQUEST']._serialized_end=2741
+  _globals['_SETPLACECOMMENTRESPONSE']._serialized_start=2743
+  _globals['_SETPLACECOMMENTRESPONSE']._serialized_end=2768
+  _globals['_ADDPLACEMATCHREQUEST']._serialized_start=2770
+  _globals['_ADDPLACEMATCHREQUEST']._serialized_end=2860
+  _globals['_ADDPLACEMATCHRESPONSE']._serialized_start=2862
+  _globals['_ADDPLACEMATCHRESPONSE']._serialized_end=2885
+  _globals['_DELETEPLACEMATCHREQUEST']._serialized_start=2887
+  _globals['_DELETEPLACEMATCHREQUEST']._serialized_end=2980
+  _globals['_DELETEPLACEMATCHRESPONSE']._serialized_start=2982
+  _globals['_DELETEPLACEMATCHRESPONSE']._serialized_end=3008
+  _globals['_ACQUIREPLACEREQUEST']._serialized_start=3010
+  _globals['_ACQUIREPLACEREQUEST']._serialized_end=3050
+  _globals['_ACQUIREPLACERESPONSE']._serialized_start=3052
+  _globals['_ACQUIREPLACERESPONSE']._serialized_end=3074
+  _globals['_RELEASEPLACEREQUEST']._serialized_start=3076
+  _globals['_RELEASEPLACEREQUEST']._serialized_end=3152
+  _globals['_RELEASEPLACERESPONSE']._serialized_start=3154
+  _globals['_RELEASEPLACERESPONSE']._serialized_end=3176
+  _globals['_ALLOWPLACEREQUEST']._serialized_start=3178
+  _globals['_ALLOWPLACEREQUEST']._serialized_end=3230
+  _globals['_ALLOWPLACERESPONSE']._serialized_start=3232
+  _globals['_ALLOWPLACERESPONSE']._serialized_end=3252
+  _globals['_CREATERESERVATIONREQUEST']._serialized_start=3255
+  _globals['_CREATERESERVATIONREQUEST']._serialized_end=3437
+  _globals['_CREATERESERVATIONREQUEST_FILTERSENTRY']._serialized_start=3362
+  _globals['_CREATERESERVATIONREQUEST_FILTERSENTRY']._serialized_end=3437
+  _globals['_CREATERESERVATIONRESPONSE']._serialized_start=3439
+  _globals['_CREATERESERVATIONRESPONSE']._serialized_end=3509
+  _globals['_RESERVATION']._serialized_start=3512
+  _globals['_RESERVATION']._serialized_end=3973
+  _globals['_RESERVATION_FILTER']._serialized_start=3732
+  _globals['_RESERVATION_FILTER']._serialized_end=3844
+  _globals['_RESERVATION_FILTER_FILTERENTRY']._serialized_start=3799
+  _globals['_RESERVATION_FILTER_FILTERENTRY']._serialized_end=3844
+  _globals['_RESERVATION_FILTERSENTRY']._serialized_start=3362
+  _globals['_RESERVATION_FILTERSENTRY']._serialized_end=3437
+  _globals['_RESERVATION_ALLOCATIONSENTRY']._serialized_start=3923
+  _globals['_RESERVATION_ALLOCATIONSENTRY']._serialized_end=3973
+  _globals['_CANCELRESERVATIONREQUEST']._serialized_start=3975
+  _globals['_CANCELRESERVATIONREQUEST']._serialized_end=4016
+  _globals['_CANCELRESERVATIONRESPONSE']._serialized_start=4018
+  _globals['_CANCELRESERVATIONRESPONSE']._serialized_end=4045
+  _globals['_POLLRESERVATIONREQUEST']._serialized_start=4047
+  _globals['_POLLRESERVATIONREQUEST']._serialized_end=4086
+  _globals['_POLLRESERVATIONRESPONSE']._serialized_start=4088
+  _globals['_POLLRESERVATIONRESPONSE']._serialized_end=4156
+  _globals['_GETRESERVATIONSRESPONSE']._serialized_start=4158
+  _globals['_GETRESERVATIONSRESPONSE']._serialized_end=4227
+  _globals['_GETRESERVATIONSREQUEST']._serialized_start=4229
+  _globals['_GETRESERVATIONSREQUEST']._serialized_end=4253
+  _globals['_COORDINATOR']._serialized_start=4256
+  _globals['_COORDINATOR']._serialized_end=5746
 # @@protoc_insertion_point(module_scope)
diff --git a/labgrid/remote/grpc/__init__.py b/labgrid/remote/grpc/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/labgrid/remote/grpc/interceptor/__init__.py b/labgrid/remote/grpc/interceptor/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/labgrid/remote/grpc/interceptor/client.py b/labgrid/remote/grpc/interceptor/client.py
new file mode 100644
index 000000000..478c6dd63
--- /dev/null
+++ b/labgrid/remote/grpc/interceptor/client.py
@@ -0,0 +1,32 @@
+from typing import Optional
+
+from grpc.aio import ClientCallDetails, ClientInterceptor, StreamStreamClientInterceptor, UnaryUnaryClientInterceptor
+
+from labgrid.remote.identity import HOSTNAME_KEY, USER_AGENT_KEY, USERNAME_KEY
+
+
+class BaseIdentityClientInterceptor(ClientInterceptor):
+    def __init__(self, username: Optional[str], hostname: str, user_agent: Optional[str]):
+        super().__init__()
+        self.username = username
+        self.hostname = hostname
+        self.user_agent = user_agent
+
+    def _inject(self, client_call_details: ClientCallDetails):
+        if self.username:
+            client_call_details.metadata.add(USERNAME_KEY, self.username)
+        client_call_details.metadata.add(HOSTNAME_KEY, self.hostname)
+        if self.user_agent:
+            client_call_details.metadata.add(USER_AGENT_KEY, self.user_agent)
+
+
+class IdentityClientUnaryUnaryInterceptor(UnaryUnaryClientInterceptor, BaseIdentityClientInterceptor):
+    async def intercept_unary_unary(self, continuation, client_call_details, request):
+        self._inject(client_call_details)
+        return await continuation(client_call_details, request)
+
+
+class IdentityClientStreamStreamInterceptor(StreamStreamClientInterceptor, BaseIdentityClientInterceptor):
+    async def intercept_stream_stream(self, continuation, client_call_details, request_iterator):
+        self._inject(client_call_details)
+        return await continuation(client_call_details, request_iterator)
diff --git a/labgrid/remote/grpc/interceptor/server.py b/labgrid/remote/grpc/interceptor/server.py
new file mode 100644
index 000000000..3727fced6
--- /dev/null
+++ b/labgrid/remote/grpc/interceptor/server.py
@@ -0,0 +1,33 @@
+import contextvars
+import logging
+from asyncio import iscoroutine
+
+from grpc.aio import ServerInterceptor
+
+from labgrid.remote.identity import ClientIdentity, NoIdentityPresent
+
+
+class IdentityServerInterceptor(ServerInterceptor):
+    def __init__(self, client_identity_contextvar: contextvars.ContextVar):
+        super().__init__()
+        self.client_identity_contextvar = client_identity_contextvar
+
+    async def intercept_service(self, continuation, handler_call_details):
+        # continuation may return a handler
+        # OR an awaitable depending on grpcio build
+        maybe_handler = continuation(handler_call_details)
+        handler = await maybe_handler if iscoroutine(maybe_handler) else maybe_handler
+        if handler is None:
+            return None
+
+        metadata = handler_call_details.invocation_metadata
+        logging.debug(metadata)
+
+        try:
+            client_identity = ClientIdentity.from_metadata(metadata)
+            logging.debug(client_identity)
+            self.client_identity_contextvar.set(client_identity)
+        except NoIdentityPresent:
+            pass
+
+        return handler
diff --git a/labgrid/remote/identity.py b/labgrid/remote/identity.py
new file mode 100644
index 000000000..442fc755d
--- /dev/null
+++ b/labgrid/remote/identity.py
@@ -0,0 +1,65 @@
+import contextvars
+import logging
+from typing import Optional
+
+from labgrid.remote.common import get_metadata_single_value_by_key
+
+USERNAME_KEY = "x-lg-username"
+HOSTNAME_KEY = "x-lg-hostname"
+USER_AGENT_KEY = "x-lg-user-agent"
+
+
+class NoIdentityPresent(Exception):
+    """Raised when metadata-based identity information is missing from the request."""
+
+
+class ClientIdentity:
+    """Represents the identity of a connected client, derived from gRPC metadata."""
+
+    def __init__(self, identity_id: str, user_agent: Optional[str]):
+        self.id = identity_id
+        self.user_agent = user_agent
+
+    def __str__(self):
+        return f"ClientIdentity(id={self.id}, user_agent={self.user_agent})"
+
+    @classmethod
+    def from_metadata(cls, metadata: tuple):
+        """Construct a ClientIdentity from gRPC request metadata.
+
+        Args:
+            metadata: A sequence of (key, value) pairs from the gRPC context.
+
+        Returns:
+            A ClientIdentity with id set to ``hostname/username`` (or just
+            ``hostname`` if no username is present) and (optional) user_agent.
+
+        Raises:
+            NoIdentityPresent: If the hostname key is missing from metadata.
+        """
+        username = get_metadata_single_value_by_key(metadata, USERNAME_KEY)
+        hostname = get_metadata_single_value_by_key(metadata, HOSTNAME_KEY)
+        user_agent = get_metadata_single_value_by_key(metadata, USER_AGENT_KEY)
+
+        if not hostname:
+            raise NoIdentityPresent()
+
+        if username:
+            return cls(f"{hostname}/{username}", user_agent)
+
+        return cls(hostname, user_agent)
+
+
+def infer_peer_identity(clients, context, identity_contextvar: contextvars.ContextVar[Optional[ClientIdentity]]):
+    logger = logging.getLogger("infer_peer_identity")
+
+    user = identity_contextvar.get()
+    if user:
+        logger.debug("identity sourced from metadata")
+        return user.id
+
+    try:
+        logger.debug("identity sourced from self.clients")
+        return clients[context.peer()].name
+    except KeyError:
+        raise
diff --git a/labgrid/remote/proto/labgrid-coordinator.proto b/labgrid/remote/proto/labgrid-coordinator.proto
index e0585f7e1..8d633b160 100644
--- a/labgrid/remote/proto/labgrid-coordinator.proto
+++ b/labgrid/remote/proto/labgrid-coordinator.proto
@@ -43,7 +43,7 @@ service Coordinator {
 message ClientInMessage {
   oneof kind {
     Sync sync = 1;
-    StartupDone startup = 2;
+    StartupDone startup = 2 [deprecated = true];
     Subscribe subscribe = 3;
   };
 };
@@ -53,6 +53,8 @@ message Sync {
 };
 
 message StartupDone {
+  option deprecated = true;
+
   string version = 1;
   string name = 2;
 };
@@ -82,7 +84,7 @@ message UpdateResponse {
 message ExporterInMessage {
   oneof kind {
     Resource resource = 1;
-    StartupDone startup = 2;
+    StartupDone startup = 2 [deprecated = true];
     ExporterResponse response = 3;
   };
 };
diff --git a/pyproject.toml b/pyproject.toml
index 499d1f087..153640e1e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -84,6 +84,7 @@ dev = [
 
     # additional dev dependencies
     "psutil>=5.8.0",
+    "pytest-asyncio==1.3.0",
     "pytest-benchmark>=4.0.0",
     "pytest-cov>=3.0.0",
     "pytest-dependency>=0.5.1",
@@ -121,6 +122,8 @@ packages = [
     "labgrid.pytestplugin",
     "labgrid.remote",
     "labgrid.remote.generated",
+    "labgrid.remote.grpc",
+    "labgrid.remote.grpc.interceptor",
     "labgrid.resource",
     "labgrid.strategy",
     "labgrid.util",
diff --git a/tests/test_interceptor_client.py b/tests/test_interceptor_client.py
new file mode 100644
index 000000000..eb8623618
--- /dev/null
+++ b/tests/test_interceptor_client.py
@@ -0,0 +1,73 @@
+import pytest
+
+from labgrid.remote.grpc.interceptor.client import (
+    BaseIdentityClientInterceptor,
+    IdentityClientUnaryUnaryInterceptor,
+    IdentityClientStreamStreamInterceptor,
+)
+from labgrid.remote.identity import USERNAME_KEY, HOSTNAME_KEY, USER_AGENT_KEY
+
+
+class DummyMetadata:
+    def __init__(self):
+        self.items = []
+
+    def add(self, key, value):
+        self.items.append((key, value))
+
+
+class DummyClientCallDetails:
+    def __init__(self):
+        self.metadata = DummyMetadata()
+
+
+def test_base_identity_client_interceptor_injects_all_fields():
+    interceptor = BaseIdentityClientInterceptor(
+        username="test_username",
+        hostname="test_hostname",
+        user_agent="test_agent",
+    )
+
+    client_call_details = DummyClientCallDetails()
+
+    interceptor._inject(client_call_details)
+
+    assert client_call_details.metadata.items == [
+        (USERNAME_KEY, "test_username"),
+        (HOSTNAME_KEY, "test_hostname"),
+        (USER_AGENT_KEY, "test_agent"),
+    ]
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    "impl,method",
+    [
+        (IdentityClientUnaryUnaryInterceptor, "intercept_unary_unary"),
+        (IdentityClientStreamStreamInterceptor, "intercept_stream_stream"),
+    ],
+)
+async def test_client_interceptor_implementations(impl, method):
+    interceptor = impl("test_username", "test_hostname", "test_agent")
+
+    client_call_details = DummyClientCallDetails()
+    request_or_iterator = object()
+    sentinel_response = object()
+
+    received = {}
+
+    async def continuation(ccd, req):
+        received["ccd"] = ccd
+        received["req"] = req
+        return sentinel_response
+
+    interceptor_method = getattr(interceptor, method)
+    result = await interceptor_method(continuation, client_call_details, request_or_iterator)
+
+    assert result is sentinel_response
+    assert received["ccd"] is client_call_details
+    assert client_call_details.metadata.items == [
+        (USERNAME_KEY, "test_username"),
+        (HOSTNAME_KEY, "test_hostname"),
+        (USER_AGENT_KEY, "test_agent"),
+    ]
diff --git a/tests/test_interceptor_server.py b/tests/test_interceptor_server.py
new file mode 100644
index 000000000..0b9741712
--- /dev/null
+++ b/tests/test_interceptor_server.py
@@ -0,0 +1,33 @@
+import contextvars, pytest
+from types import SimpleNamespace
+from unittest.mock import Mock
+from labgrid.remote.grpc.interceptor.server import IdentityServerInterceptor
+
+
+@pytest.fixture
+def cv():
+    return contextvars.ContextVar("client_identity", default=None)
+
+
+@pytest.fixture
+def interceptor(cv):
+    return IdentityServerInterceptor(cv)
+
+
+def handler_call_details(metadata):
+    return SimpleNamespace(invocation_metadata=tuple(metadata))
+
+
+@pytest.mark.asyncio
+async def test_server_interceptor_sets_contextvar(interceptor, cv):
+    handler = object()
+    continuation = Mock(return_value=handler)
+
+    metadata = (("x-lg-hostname", "h"), ("x-lg-username", "u"), ("x-lg-user-agent", "ua"))
+
+    ret = await interceptor.intercept_service(continuation, handler_call_details(metadata))
+    assert ret is handler
+
+    identity = cv.get()
+    assert identity.id == "h/u"
+    assert identity.user_agent == "ua"
diff --git a/tests/test_remote.py b/tests/test_remote.py
index 76a1da434..76021c63f 100644
--- a/tests/test_remote.py
+++ b/tests/test_remote.py
@@ -1,4 +1,9 @@
+import warnings
+
 import pexpect
+import pytest
+
+from labgrid.remote.common import get_metadata_single_value_by_key
 
 
 def test_client_help():
@@ -48,3 +53,50 @@ def test_exporter_coordinator_becomes_unreachable(coordinator, exporter):
     assert exporter.exitstatus == 100
 
     coordinator.resume_tree()
+
+
+def test_get_metadata_single_value_by_key_returns_value_for_existing_key():
+    metadata = [("key1", "value1"), ("key2", "value2")]
+    assert get_metadata_single_value_by_key(metadata, "key1") == "value1"
+    assert get_metadata_single_value_by_key(metadata, "key2") == "value2"
+
+
+def test_get_metadata_single_value_by_key_returns_none_for_missing_key():
+    metadata = [("key1", "value1")]
+    assert get_metadata_single_value_by_key(metadata, "other") is None
+
+
+def test_get_metadata_single_value_by_key_returns_none_for_empty_metadata():
+    assert get_metadata_single_value_by_key((), "key") is None
+
+
+def test_get_metadata_single_value_by_key_returns_none_for_none_metadata():
+    assert get_metadata_single_value_by_key(None, "key") is None
+
+
+def test_get_metadata_single_value_by_key_returns_first_value_on_duplicate_keys():
+    metadata = [("key", "first"), ("key", "second")]
+    with pytest.warns(UserWarning, match="Multiple metadata KV pairs"):
+        result = get_metadata_single_value_by_key(metadata, "key")
+        assert result == "first"
+
+
+def test_get_metadata_single_value_by_key_no_warning_on_single_match():
+    metadata = [("key", "value")]
+    with warnings.catch_warnings(record=True) as caught:
+        warnings.simplefilter("always")
+        get_metadata_single_value_by_key(metadata, "key")
+        assert len(caught) == 0
+
+
+def test_get_metadata_single_value_by_key_returns_first_value_for_non_adjacent_duplicates():
+    metadata = [("key", "first"), ("other", "value"), ("key", "second")]
+    with pytest.warns(UserWarning, match="Multiple metadata KV pairs"):
+        result = get_metadata_single_value_by_key(metadata, "key")
+        assert result == "first"
+
+
+def test_get_metadata_single_value_by_key_is_case_sensitive():
+    metadata = [("Key", "value")]
+    assert get_metadata_single_value_by_key(metadata, "key") is None
+    assert get_metadata_single_value_by_key(metadata, "Key") == "value"